This charger was designed for the KangerTech e-Smart Battery - 320mAh, but it will charge any size or model of 510 battery including XL or Jumbo 510 Batteries.

To use this product simply screw the battery onto one end of the charger and plug the other end into any USB port.  LED will turn red while charging and will turn back to green when fully charged.  It is not a good idea to leave batteries attached to charger longer than necessary.  This could shorten the lifespan of the battery and the charger. 

Output for this charger is rated at 200mAh